thumb|Leopold Hofmann, was an Austrian composer of classical music.|341x341px Leopold Hofmann (also Ludwig Hoffman, Leopold Hoffman, Leopold Hoffmann; 14 August 1738 – 17 March 1793) was an Austrian c
1. Compute SHA-256 of OTSCanonicalRecord value → must equal OTSHash 2. Open OTSProofURL → extract Bitcoin block number → must equal OTSBitcoinBlock 3. GET OTSBitcoinBlockVerifyURL → returns the Bitcoin block hash at height OTSBitcoinBlock; GET https://blockstream.info/api/block/{that hash} → its timestamp must match OTSTimestamp 4. Read CopyrightID inside OTSCanonicalRecord → must equal the CopyrightID above 5. GET OTSVerificationAPI → pre-computed 6-check result from server 6. If all match: this entity was registered on CopyrightChains at OTSTimestamp, independently verifiable on Bitcoin Note: an OTS proof may carry multiple Bitcoin attestations; OTSBitcoinBlock is the earliest confirmed one — a later attestation inside the proof corroborates it and is not a mismatch
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbe32b70a15be041cf17216ad474bf8367f2cd9e62a9701bc2c03b5d860c38d6f. Chain 2 (Bitcoin): anchored in block 953610 (2026-06-14T07:58:09Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/140d5ba3-961b-4669-a8a1-e993715d543c.json and https://artists.proofprofile.net/proofs/artist/140d5ba3-961b-4669-a8a1-e993715d543c.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Flute Concerto in A Major, Badley A1: III. Allegro
1. Confirm isrcCode identifies the recording in the pre-2022 source corpus and cc-db-prod record 2. GET OTSVerificationAPI → server-side canonical-record, hash, and attestation checks must pass 3. GET OTSBitcoinBlockVerifyURL → returns the Bitcoin block hash at height OTSBitcoinBlock; GET https://blockstream.info/api/block/{that hash} → its timestamp must match OTSTimestamp 4. Confirm CopyrightID is the CopyrightChains transaction hash 5. If all match: the cc-db-prod record is independently anchored on Bitcoin at OTSTimestamp Note: an OTS proof may carry multiple Bitcoin attestations; OTSBitcoinBlock is the earliest confirmed one — a later attestation inside the proof corroborates it and is not a mismatch
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x51e527658f73749385a26b7d56e0ca0e3ad5213640a83c24c1c47e5cdc7da766. Chain 2 (Bitcoin): anchored in block 956889 (2026-07-06T06:56:49Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/HKI191830309.
Hofmann: Concerti per Flauto e Orchestra
Hofmann, L.: Oboe Concertos / Concertos for Oboe and Harpsichord
Oboe Concerto in G Major (Badley G1): Adagio
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xac8758b7675832d22c2696d55271656e324a397ed7fa40fb004abadb886050c6. Chain 2 (Bitcoin): anchored in block 960288 (2026-07-30T17:41:38Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/HKI190218911.
Flute Concerto in D Major, Badley D4: II. Andante ma non molto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x92b691abbb09defd436d84a7dc2d8934057877ff05e5676ae1527cf80c32175f. Chain 2 (Bitcoin): anchored in block 960273 (2026-07-30T15:42:38Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/HKI190036408.
Flute Concerto in D Major, Badley D6: II. Adagio
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbab050d8b6f465cdad93d6d1bd51b46d125fd2200d1dabc46d47eeed0b96bf78. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/HKI190041511.
Cello Concerto in D Major, Badley D3: I. Allegro moderato
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1b2f78df9b1b0c080ae6e5b3b6456ba3b3d5627f6abf083b9c8dbe4c7c3b2a8b. Chain 2 (Bitcoin): anchored in block 960340 (2026-07-31T03:15:04Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/HKI199612301.
Cello Concerto in D Major, Badley D3: III. Allegro molto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x710b4898713b87bed22f61ffb8bbb4a931dcc4e7c2b03cf0c21c25eb390f3b8f. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/HKI199612303.
Cello Concerto in C Major, Badley C3: II. Adagio
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa64c9c41fdbc0e30134bc7c22e4f8d245e390617bd6f071a2ab289bd3be38d91. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/HKI199612305.
Cello Concerto in C Major, Badley C3: III. Vivace
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2ecfcd61c5e0953ffb3a0a7c11d5ef293053abb5bcd382cfe4b979b2f1644df3. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/HKI199612306.
Cello Concerto in D Major, Badley D1: II. Andante ma non molto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x74613e0ceaf11198b5be65480d214de588286102f0a20b60318236554cbbdaf8. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/HKI199612308.
Cello Concerto in D Major, Badley D1: III. Vivace
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5c5762341d298cc027583fd93efcae931abc0e9a94fad0721c1aab05c13e4252. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/HKI199612309.
Cello Concerto in C Major, Badley C1: I. Tempo giusto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xace9927e5e15a58d1c6e4e5af7db70b26fd6ad0de4c5e2ef911effe2fa9341f3. Chain 2 (Bitcoin): anchored in block 960441 (2026-07-31T17:29:52Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/HKI199612310.
Cello Concerto in C Major, Badley C1: II. Adagio ma non molto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc7f60c60a9b2f8a55f6de42b29a6b0ac263e9fbcea83cfceb44960ee7fdac85d. Chain 2 (Bitcoin): anchored in block 960494 (2026-08-01T01:44:32Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/HKI199612311.
Sinfonia in B-Flat Major, Badley Bb1: II. Andante
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x32f543d6649f8c1f75c5d3f0e130755882c2d574ba26be6147b0101d57d47831. Chain 2 (Bitcoin): anchored in block 960344 (2026-07-31T04:14:58Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/HKI199611402.
Sinfonia in F Major, Badley F1: III. Menuet
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa35c74ff145c1bfe17823194c1e3febf3e01a6f02c08a112381f0e9819178585. Chain 2 (Bitcoin): anchored in block 956889 (2026-07-06T06:56:49Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/HKI199611406.
Hofmann: Concerto pour flûte (Formerly Attributed to Joseph Haydn as Hob. VIIf:D1, Mono Version)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9a724b492569cb478af581e307151ccdcb6020ae0d60f895a45e0d95f82be995. Chain 2 (Bitcoin): anchored in block 960222 (2026-07-30T07:48:45Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEE470900365.